A method for automatically measuring wheel geometric parameters by laser scanning is presented. The running surface of wheel is scanned by the line structured light vision sensors, and the geometric parameters including wheel diameter, flange thickness, tread wear and rim width are calculated after processing the point cloud. This is different from the traditional methods which measures the geometric parameters by comparing a measured profile to the standard profile of wheel tread.This method is not strict with the relative position between the line structured light and the wheel. The feasibility of this method is demonstrated by experimental results.